Alternating-eiectric-current interrupter



March 31, 1931. G. ELLISON ET AL 1,798,319

ALTERNATING ELECTRIC CURRENT INTERRUPTER Filed Feb. 25, 1930 25 forms one Patented Mar. 31, 1931 UNITED STATES PATENT canoe enoaen ELLISON AND nuns aunnnson, or BIBMINGHAI, n'nenmn ALTERNATING-ELECTRIC-CURBENT INTERBUP'IER Application filed February 25, 1930, Serial N 0,-

This invention has for its object to provide improved means for interrupting alternating electric currents.

The invention comprisesthe combination of a plurality of coaxial contact pieces which are arranged in series and are contained in compartments separated by insulating diaphragms, and means for producing a radial magnetic field in association with the contact 10 pieces.

The accompanying drawing illustrates diagrammatically one mode of carrying the invention into efiect.

Referring to the diagram, we employ a plurality of movable annular contact pieces a which are arranged coaxially. Preferably each contact piececonsists of a ring of copper which is electro-plated with a coating of zinc or cadmium.-

A convenient number of these contact pieces is employed and each is carried by a disc or diaphragm b of flexible insulating ma: terial. The contact pieces are contained within an annular iron container 0 which ole of an electromagnet excited by a winding (1 in series with the contact pieces, the other pole being formed by a central bar e, the arrangement giving a radial magnetic field across the space between the parts 0, e. The diaphragms b are attached at their inner and outer peripheries to the parts 0, e in any convenient manner, and they form a plurality of chambers each contain- 'ing the adjacent parts of a pair of contact pieces. Preferably each diaphragm is perforated by oppositely arranged holes 7 and the container 0 is also perforated as s own at g. The whole may be immersed in oil. The contact piece It at one end of the series 40 is fixed, and the one 2' at the other end is carried on a movable member 7' which can be actuated in any convenient manner. Also the contact pieces *h, i are connected to the circuit to be controlled by any appropriate means. The circuit is closed when I y means of the member, 7 all the contact pieces are pressed together. On withdrawing the member the contacts are separated, either b gravity, or the elasticity of the diaphra' or under the action of springs, or

rupters, the combination of a 431,294, and in Great Britain March 4, 1929. 4

by any other suitable means,.and, under the the faces of the contact pieces, and is thereby.

rapidly extinguished. The amount ofsepa ration allowed between each pair of contacts need not be large, from three to eight thousandths of an inch being usually sufiicient.

The number of .movable contact pieces provided depends upon the voltage of the system to be controlled, an allowance of about four hundred volts per contact being usually sat isfactory. Y Y

The invention is especially adapted for the switches used for controlling large amounts of electrical energy, but it may be applied to any system in which 1t is necessary to avoid Y excessive arcing.

It will be understoodthat the invention is not limited to the exampleabove described, and the constructional details may be varied as required.

Having thus described'our invention what we claim as newand desire to secure by Letters Patent is -1. In alternating electric current inter-' plurality of coaxial contact pieces arranged in series, an

outer container, diaphragms of insulating material arranged across the interior of the container and forming compartments each of which encloses a pair of contact ieces, (a contact piece being secured to eac side of each diaphragm and interconnected), and means for producing a radial magnetlc field in association with the contact pieces, substantially as described.

2. In alternating electric current interrupters, the combination f an outer iron container, a central axial iron core, diaof insulating material arrangedphragms para lel with each other and dividing-the space between the core and container into 'a number of separate compartments, a pair of coaxial annular contact pieces secured in electrical connection with each other to the opposite sides of each diaphragm, the whole of the contact rings forming a grou of contacts in series with each other, a .fixe A contact situated within the container, at one end of the said group of contacts, a movable contact situated at the other end of the group whereby all the contact rings can be pressed into contact with each other, and a magnetic winding on the core substantially as described. In testimony whereof we have signed our names to this specification;

GEORGE ELLISON. JAMES ANDERSON. 

